Automated feedback loop manages variations
Schlumberger recommended a system comprising three pieces of equipment
to enable closed-loop control of the PCP: a real-time flowmeter, programmable
logic controller (PLC), and variable speed drive (VSD).
To determine real-time flow of water and gas at surface, engineers
recommended installing a wedge meter, which measures the differential pressure
across a V-shaped wedge placed in the flow stream. Volumetric flow rate is
calculated from the measured differential pressure.
The data from the wedge meter is delivered to the KUDU PCP Manager unit,
which is a PLC with a proprietary algorithm that assesses theoretical versus
actual flow rates and adjusts the VSD to optimize well production.
Water, gas production, and PCP survivability increase
After installing the digital automation equipment in the well and
eliminating water buildup, the flowing bottomhole pressure stabilized at a
consistent 35 psi, resulting in a 58% increase in gas production. Average daily
water volume almost doubled, while maintaining sufficient water above the
PCP.
Pump cavity fillage stabilized at nearly 100%, improving PCP lifetime
from a few weeks or months to years; the PCP continues to operate as planned
after nearly 3 years. The operator extended this solution to 80 other wells,
where similar results have been achieved.
While improving production and total cost of ownership, the enhanced
performance also reduced personnel requirements in the field, eliminating the
need for periodic fluid-level shots and visits to verify performance. This
saved the operator considerable opex and greatly decreased road mileage and
safety risks.